On-stream sample collecting mechanism for high pressure liquids

ABSTRACT

A safe and efficient mechanism for taking liquid samples, as crude oil, at pressures up to 250 psig and transferring them to an atmospheric pressure container for future analysis comprises a double ended through-flow sample holding reservoir connected to an eight port rotary valve for periodically having its contents blown into a depressurizing vessel from which the liquid at atmospheric pressure flows by gravity to a two ended flow-through sample vial to purge it with a fresh sample. The latter vial permits transfer of an aliquot by a conventional automatic sampler for gas chromatographs or the like to an analytical instrument for subsequent analysis.

United States Patent [1 1 1111 3,780,590 Stamm Dec. 25, 1973 ON-STREAM SAMPLE COLLECTING MECHANISM FOR HIGH PRESSURE LIQUIDS Primary Examiner- 5. Clement Swisher Attorney-Thomas H. Whaley et al.

[75] Inventor: Ralph Stamm, Port Arthur, Tex. 57] ABSTRACT [73] Asslgnee: Texaco New York A safe and efficient mechanism for taking liquid sam- 22 Filed; Oct 30 1972 ples, as crude oil, at pressures up to 250 psig and 2 transferring them to an atmospheric pressure con- [21] Appl. No.: 302,153 tainer for future analysis comprises a double ended I through-flow sample holding reservoir connected to 521 u.s. c1. 73/422 TC an eight P rotary valve for Periodically having its 511 Int. Cl. G0ln 1/10 contents blown into a depressurizing vessel from 58 Field ofSearch' 73/422 R, 422 cc, which the liquid at atmospheric Pressure flows y 73/422 TC gravity to a two ended flow-through sample vial to purge it with a fresh sample. The latter vial permits [56] Refe Cit d transfer of an aliquot by a conventional automatic UNITED STATES PATENTS sampler for gas chromatographs or the like to an ana- 3,064,481 11/1962 Alexander 73/422 TC 1y Instrument for Subsequent analysls' 3,343,421 9/1967 Miller 73/422 GC 15 Claims, 2 Drawing Figures /0 1 I a ed 0700/5 Mr 13 a AOTA/FV VAL VE CRUDE //V 1 ON-STREAM SAMPLE COLLECTING MECHANISM FOR HIGH PRESSURE LIQUIDS BACKGROUND OF THE INVENTION Conventional process gas chromatographic systems for collecting samples of process fluid utilize automatically operated valves which cannot stand up under the high temperatures required to vaporize heavy fluids such as crude oil and remain leak-free for any extended period of operation. At temperatures above 225C. the valve sealing materials begin to soften and decompose and the sample circulated through the valves starts to degrade and vaporize prematurely leading to bubbles and non-reproducible sampling.

This sample collecting mechanism was, therefore, developed as an aid in the on-stream simulated distillation analysis of crude oil by gas chromatography. Because of the nature of the sample, ordinary process gas chromatographs using sample valves could not provide adequate performance due to the temperature limits of the materials of which the valves are constructed. Process gas chromatographs are also not capable of adequate column temperature programming performance. Using the mechanism described herein allowed the desired on-stream simulated distillation analysis of crude oil to be performed automatically by means of a high performance laboratory type gas chromatograph with syringe injection. With syringe. injection, injection temperatures up to 375C. can be easily obtained.

OBJECTS OF THE INVENTION Accordingly, a primary object of this invention is to provide complete isolation between high pressure and low pressure fluids for safe operation and easy utilization of collected fluid.

Another primary object of this invention is to provide a mechanism for collecting samples of high pressure fluid for use by a standard laboratory microliter size syringe for a gas chromatograph, for an automated wet chemical analysis of a process stream, and the like.

Another object of this invention is to provide a mechanism for collecting samples of a high pressure fluid for flow-through spectrophotometer cells which are usually incapable of pressurized operation.

Still another object of this invention is to provide a mechanism for collecting samples of high pressure fluids and simultaneously permitting the escape of highly volatile components that are held in the fluid only through pressure and not by inherent solubility.

A further object of this invention is to provide a mechanism for collecting high pressure samples of fluid that is easy to operate, is of simple configuration, is economical to build and assemble, and is of greater efficiency for the collection of samples of such a fluid.

Other objects and various advantages of the disclosed on-stream sample collection mechanism for high pressure liquids will be apparent from the following detailed description, together with the accompanying drawings, submitted for purposes of illustration only and not intended to define the scope of the invention, reference being had for that purpose to the subjoined claims.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings diagrammatically illustrate by way of example, not by way of limitation, one form of the invention wherein like reference numerals designate corresponding parts in the several views in which:

FIG. 1 is a schematic diagrammatic view of a mechanism for collecting samples of high pressure fluids while in the first stage of operation; and

FIG. 2 is a schematic diagrammatic view of the device of FIG. 1 shown in the second stage of operation.

DESCRIPTION OF THE PREFERRED EMBODIMENT The invention disclosed herein, the scope of which being defined in the appended claims is not limited in its application to the details of construction and arrangement of parts shown and described, since the invention is capable of other embodiments and of being practiced or carried out in various other ways. Also, it is to be understood that the phraseology or terminology employed here is for the purpose of description and not of limitation. Further, many modifications and variations of the invention as hereinbefore set forth will occur to those skilled in the art. Therefore, all such modifications and variations which are within the spirit and scope of the invention herein are included and only such limitations should be imposed as are indicated in the appended claims.

FIG. 1 discloses the new on-stream sample collecting mechanism 10 connected to high pressure fluid inlet line 11 and outlet line 12, the lines having pressure gauges 13a, 13b, respectively, thereon.

An eight port rotary valve 14, FIGS. 1 and 2, controllably interconnects a pressurized inert gas storage container 15, as of nitrogen for example, with a double ended through-flow sample holding reservoir or crude oil sample vessel 16, andinterconnects the reservoir controllably with a depressurizing vessel 17. From the depressurizing vessel, the fluid flows to a two ended flow-through sample vial 18, with the purged old sample flowing out to a waste sample storage drum 19.

In greater details, theinert gas container 15, FIG. 1, is pressurized to a suitable, operable pressure, as 15 psig for example, with rotary valve 14 in the first position illustrated. Likewise with the rotary valve so positioned, the through-flow double ended sample holding reservoir 16 is purged with a sample liquid measured for rate through a flow meter20 and at pressures indicated by gauges 13a and 13b. At this rotary valve setting, the rest of the system is inactive except for some 'fluid flow through a by-pass line and valve 21.

Examplary sizes for the containers are cc. (cubic centimeters) for each of the containers 15 and 16, cc. for the depressurized vessel 17, 3 cc. for the vial 18, and 55 gallons for the waste sample storage drum 19.

At a predetermined time an electrical signal is applied to the eight port rotary valve 14, FIG. 1, causing it to rotate to its alternate second position of FIG. 2. Then pressurized gas from container 15 forces the high pressure (up to 250 psig) trapped sample liquid from holding reservoir 16 to large depressurizing vessel 17 which is vented to the atmosphere by line 22. Vessel 17 is positioned above vial 18 so that the sample liquid will flow by gravity straight to the vial. The sample liquid flows through vial l8 purging it with a fresh sample. The vial is a stainless steel or aluminum container with sured portion of the oil sample, mechanically withdraws the syringe and moves it to a gas chromatograph sample port, and injects the aliquot into the chromatograph.

When sample vial 18 is purged with a fresh sample of liquid, the old sample flows by gravity or is siphoned to the waste sample storage drum 19.

Likewise with the rotary valve 14 in the second position of FIG. 2, by-pass flow of the liquid flow is maintained through ports 3 and 4 of the eight port rotary valve 14. While the inert or nitrogen gas source 23 is connected with the closed pipe 24 in the second position of the rotary valve of FIG. 2, the input port 6 of the depressurizing vessel 17 is connected to the closed pipe 24 when the rotary valve is rotated to the first position of FIG. 1.

Use of the single eight port valve for all switching functions provides a high degree of operational safety in that malfunctions which could result in connection of the highpressure fluid to the low pressure sample vial are not possible.

Thus accordingly, it will be seen that the present onstream sample collectingmechanism for high pressure liquids operates in a manner which meets each of the objects set forth hereinbefore.

While only one embodiment of the invention has been disclosed, it will be evident that various modifications are possible in the arrangement and construction of the disclosed liquid sample collecting mechanism without departing from the scope of the invention, and it is accordingly desired to comprehend within the purview of this invention such modifications as may be considered to fall within the scope of the amended claims.

I claim:

1. A mechanism for collecting a liquid sample from a high pressure liquid line means comprising,

a. liquid sample holding reservoir means for receiving liquid from the liquid line means,

b. inert pressurized gas chamber means for forcing the liquid from said sample holding reservoir means,

c. depressurizing vessel means for receiving liquid from said liquid sample holding reservoir means,

d. vial means for receiving liquid from said depressurizing vessel,

e. multiport valve means for the liquid line means for being actuatable between first and second positions, and w l f. said depressurizing vessel means being responsive to said multiport valve means for filling said vial means with a fresh charge of liquid for testing.

2. A mechanism as recited in claim 1 wherein,

a. the liquid line means is responsive to said multiport valve means when said multiport valve means is actuated to said first position for filling said liquid sample holding reservoir means with a fresh charge of liuqid. 1

3. A mechanism as recited in claim 1 wherein,

a. said inert pressurized gas chamber means is responsive to said multiport valve means when said multiport valve means is actuated to said first position for being filled from a pressurized gas source.

4. A mechanism as recited in claim 1 wherein,

a. said inert pressurized gas chamber means is responsive to said multiport valve means when said multiport valve means is actuated to said second position for expelling the liquid sample from said liquid sample holding reservoir means to said depressurizing vessel means.

5. A mechanism as recited in claim 1 wherein,

a. said liquid sample holding reservoir means is responsive to the forces of gravity for filling said vial with a fresh charge of liquid for testing.

6. A mechanism as recited in claim 1 wherein,

a. a bypass valve means responsive to said multiport valve means when actuated to said second position for bypassing the liquid in the liquid line means around said liquid sample holding reservoir means.

7. A mechanism as recited in claim 1 wherein,

a. said depressurizing vessel means has means for venting atmospheric pressure thereto for insuring that the liquid under high pressure in the liquid sample holding reservoir means be reduced to atmospheric pressure.

8. A mechanism as recited in claim 1 wherein,

a. said multiport valve means being an eight port rotary valve interconnecting said liquid line means, said inert pressure gas chamber means, said liquid sample holding reservoir means, and said depressurizing vessel means.

9. A mechanism as recited in claim 1 wherein,

a. said liquid sample holding reservoir means is responsive to said multiport valve means when said multiport valve means is actuated to said second position for expelling the liquid sample from said liquid sample holding reservoir means to said depressurizing vessel means for filling said vial means with a fresh charge of liquid for testing.

10. A mechanism for safely collecting a liquid sample from a high pressure liquid line comprising,

a. a multiport valve having first and second positions connected to the high pressure liquid line,

b. a sample holding reservoir connected to said multiport valve for being filled with a sample of liquid from said liquid line when said multiport valve is in said first position, i

c. an inert pressurized gas chamber connected to said multiport valve for supplying pressurized gas to said sample holding reservoir when said multiport valve is in said second position,

d. a depressurizing vessel connected to said multiport valve for receiving said liquid sample from said sample holding reservoir when said multiport valve is in said second position, and

e. a vial connected to said depressurizing vessel for receiving said liquid sample therefrom for future analysis.

11. A mechanism as recited in claim 10 wherein,

a. said multiport valve is an eight port rotary valve.

12. A mechanism as recited in claim 10 wherein,

a. a by-pass line is connected in the high pressure liquid line around said sample holding reservoir for sphere.

15. A mechanism as recited in claim 10 wherein,

a. said vial comprises a metal container having an inlet for receiving a fresh sample of liquid from said depressurizing vessel and an outlet for draining off the prior old liquid, and

b. said vial container being sealed with a rubber septum for insertion of a syringe into the vial for drawing off of a sample of liquid. 

1. A mechanism for collecting a liquid sample from a high pressure liquid line means comprising, a. liquid sample holding reservoir means for receiving liquid from the liquid line means, b. inert pressurized gas chamber means for forcing the liquid from said sample holding reservoir means, c. depressurizing vessel means for receiving liquid from said liquid sample holding reservoir means, d. vial means for receiving liquid from said depressurizing vessel, e. multiport valve means for the liquid line means for being actuatable between first and second positions, and f. said depressurizing vessel means being responsive to said multiport valve means for filling said vial means with a fresh charge of liquid for testing.
 2. A mechanism as recited in claim 1 wherein, a. the liquid line means is responsive to said multiport valve means when said multiport valve means is actuated to said first position for filling said liquid sample holding reservoir means with a fresh charge of liuqid.
 3. A mechanism as recited in claim 1 wherein, a. said inert pressurized gas chamber means is responsive to said multiport valve means when said multiport valve means is actuated to said first position for being filled from a pressurized gas source.
 4. A mechanism as recited in claim 1 wherein, a. said inert pressurized gas chamber means is responsive to said multiport valve means when said multiport valve means is actuated to said second position for expelling the liquid sample from said liquid sample holding reservoir means to said depressurizing vessel means.
 5. A mechanism as recited in claim 1 wherein, a. said liquid sample holding reservoir means is responsive to the forces of gravity for filling said vial with a fresh charge of liquid for testing.
 6. A mechanism as recited in claim 1 wherein, a. a by-pass valve means responsive to said multiport valve means when actuated to said second position for bypassing the liquid in the liquid line means around said liquid sample holding reservoir means.
 7. A mechanism as recited in claim 1 wherein, a. said depressurizing vessel means has means for venting atmospheric pressure thereto for iNsuring that the liquid under high pressure in the liquid sample holding reservoir means be reduced to atmospheric pressure.
 8. A mechanism as recited in claim 1 wherein, a. said multiport valve means being an eight port rotary valve interconnecting said liquid line means, said inert pressure gas chamber means, said liquid sample holding reservoir means, and said depressurizing vessel means.
 9. A mechanism as recited in claim 1 wherein, a. said liquid sample holding reservoir means is responsive to said multiport valve means when said multiport valve means is actuated to said second position for expelling the liquid sample from said liquid sample holding reservoir means to said depressurizing vessel means for filling said vial means with a fresh charge of liquid for testing.
 10. A mechanism for safely collecting a liquid sample from a high pressure liquid line comprising, a. a multiport valve having first and second positions connected to the high pressure liquid line, b. a sample holding reservoir connected to said multiport valve for being filled with a sample of liquid from said liquid line when said multiport valve is in said first position, c. an inert pressurized gas chamber connected to said multiport valve for supplying pressurized gas to said sample holding reservoir when said multiport valve is in said second position, d. a depressurizing vessel connected to said multiport valve for receiving said liquid sample from said sample holding reservoir when said multiport valve is in said second position, and e. a vial connected to said depressurizing vessel for receiving said liquid sample therefrom for future analysis.
 11. A mechanism as recited in claim 10 wherein, a. said multiport valve is an eight port rotary valve.
 12. A mechanism as recited in claim 10 wherein, a. a by-pass line is connected in the high pressure liquid line around said sample holding reservoir for bypassing liquid around said sample holding reservoir when said multiport valve is in said second position.
 13. A mechanism as recited in claim 10 wherein, a. a pressurized gas supply line is connected to said multiport valve, and b. said inert pressurized gas chamber being fillable by pressurized gas when said multiport valve is in said first position.
 14. A mechanism as recited in claim 10 wherein, a. said depressurizing vessel is vented to the atmosphere.
 15. A mechanism as recited in claim 10 wherein, a. said vial comprises a metal container having an inlet for receiving a fresh sample of liquid from said depressurizing vessel and an outlet for draining off the prior old liquid, and b. said vial container being sealed with a rubber septum for insertion of a syringe into the vial for drawing off of a sample of liquid. 